Stochastic-network Reduction and Sensitivity Techniques in a Cost Effectiveness Study of a Military Communications System

This paper describes some aspects of cost effectiveness methodology and operational research as they have been applied in a system design study for a military communications system. There are two main areas of interest from an operational research point of view:(a) The attempt to use cost effectiveness analysis as an integral part of system design.(b) The development and application of new techniques (notably in stochastic network analysis and simulation) which are potentially of much wider application.There are several ways of attacking the problem of multiple objectives encountered in a cost effectiveness analysis. These are briefly described and the preferred method of a single measure of effectiveness is discussed in detail. The measure used in the communications system design study is presented and the method of evaluating it by simulation is described. The next step after evaluation of the effectiveness is optimization and here the use of the Lagrange multipliers is introduced. This method requires iteration on the values of performance parameters and their costs and this becomes very time-consuming if a simulation must be performed each time. It is here that the novel methods of analysing networks are developed. The main use of these methods of analysis, or reduction rules, has been in reducing the size and complexity of the simulations. The technique which has contributed most to the reduction in the number of simulations required to arrive at an optimum disposition of resources is a method of carrying out a sensitivity analysis based on data collected during a single simulation run. This hybrid analytical-cum-simulation technique is discussed in detail with reference to a communications system, and its application to a wider range of problems, such as probabilistic PERT, indicated.     

Scheduling non-critical activities using multicriteria approach

In many projects the problem of selecting the start time of a non-critical activity arises. Usually it is possible to use the “as soon as possible” or “as late as possible” rules. In some situations, however, the result of such a decision depends on external factors such as exchange rate. This leads to an approach in which the problem of scheduling non-critical activities is solved using an expanded Cox–Ross–Rubinstein (CRR) binomial tree method. In the paper a bi-criteria problem of determining the start time of a non-critical activity is considered. We assume that the early start and the late start of the activity have been identified using Critical Path Method, but the project manager is free to select the time when the activity will actually be started. This decision cannot, however, be changed later, as it is associated with the allocation of key resources. Two main criteria are considered: cost and risk. While cost depends on exchange rate, risk increases with the delay of the start of the activity. The problem can be described as a dynamic process. We propose a new interactive technique for solving such a bi-criteria decision making problem under risk. The procedure uses trade-offs to identify a candidate solution. The CRR binomial method is applied to evaluate the cost of the activity.

     

Project screening with tiered evaluation

We study a Bayesian game of two-sided incomplete information in which an agent, who owns a project of unknown quality, considers proposing it to an evaluator, who has the choice of whether or not to accept it. There exist two distinct tiers of evaluation that differ in the benefits they deliver to the agent upon acceptance of a project. The agent has to select the tier to which the project is submitted for review. Making a proposal incurs a cost on the agent in the form of a submission cost. We examine the effect of changes in the payoff parameters at the two tiers of evaluation on the efficiency of the equilibrium outcome. We show that changes in these parameters that are aimed at increasing the level of self-screening exerted by the agent do not necessarily have beneficial effects either on the quality of projects submitted for review or on the quality of projects that are implemented. From a methodological viewpoint, our paper proposes a novel method of performing comparative statics in games whose equilibria are defined by a system of equations with no closed-form solution.     

Project cost dynamics for development policy-making

Cost and time overruns have been a common characteristic of development projects in many countries. This paper presents a theory of cost and time overruns based on project cost structure. The cost of a development project consists of base cost and progress cost. Base cost keeps a project ready for physical progress. Progress cost creates real physical progress on the project. This cost structure has an important inherent dynamic characteristic with implications for the efficiency and effectiveness of project management. An imbalance between annual budget and ongoing projects results in an increasing inefficiency and ineffectiveness unrelated to the quality of management of individual projects. The policy governing the starting rate of the new projects becomes very important in improving project performances. The paper also suggests some policy recommendations for commencing new projects.     

Using a risk-based approach to project scheduling: A case illustration from semiconductor manufacturing

This paper introduces a risk-based optimization method to schedule projects. The method uses risk mitigation and optimal control techniques to minimize variables such as the project duration or the cost estimate at completion. Mitigation actions reduce the risk impacts that may affect the system. A model predictive control approach is used to determine the set of mitigation actions to be executed and the time in which they are taken. A real-life project in the field of semiconductor manufacturing has been taken as an example to show the benefits of the method in a deterministic case and a Monte Carlo simulation has also been carried out.     

Evaluating IT/IS investments: A fuzzy multi-criteria decision model approach

IT/IS represents a substantial financial investment for many organizations. Whether or not to invest in new IT/IS is, therefore, a difficult decision. Simply considering human resource cost saving criteria is not enough, especially when a corporation has had many information systems. What kind of criteria should we consider when we evaluate IT/IS? How can a new IT/IS project be evaluated in an easy, cost-effective, and collective manner? We need a tool that will help decision-makers evaluate potential new investment projects. Apart from evaluating the new project per se, its compatibility and ability to integrate with an existing IT portfolio must also be considered. Hence, we propose a new approach based on the fuzzy multi-criteria decision model (FMCDM), featuring a 2-stage evaluation process with 26 criteria for IT/IS investment. All stakeholders in a corporation can decide the relative weights they give to the criteria when they evaluate a new IT/IS project by using linguistic values. Experts can also use linguistic values to evaluate all candidates easily. Only an Excel worksheet is needed to obtain an evaluation result. It is cost-effective and efficient. We conduct a case study to show how this model can be used and discuss the results.     

决策树分类模型在工程项目评标风险预警中的应用

本文将数据挖掘中的决策树分类方法运用到工程项目评标数据分析,从200多个天津市工程项目招投标打分数据中,随机抽取15个招投标项目中的67个承包商的评标专家打分数据进行分析,得到中标承包商技术和商务评分分界点,进而得到工程项目潜在风险的预警阈值,然后借助因子分析辨识出风险来源并进行预警。     

改进模糊层次分析法在初级任职教育院校教学工作评价中的应用

针对初级任职教育院校教学工作评价指标多,体系复杂,难以完全量化评估的特点,引入改进的模糊层次分析法,为指标建立权重,并用相容性指标进行矩阵一致性检验,构建了模糊评价模型,提出了初级任职教育院校教学工作评价的多目标决策问题解决方案。该方法简便可行,可靠性好,与其它评价方法相比更加客观准确。     

Evaluating environmentally conscious business practices

Corporate environmental management is becoming more strategically oriented. With increased emphasis on the natural environmental by organizational stakeholders, including governments, stockholders, customers, employees and communities, the need for explicit consideration and incorporation of environmental strategy within corporate strategy has never been more critical to the organization. With such programs as design for the environment, total quality environmental management, life cycle analysis, green supply chain management, and ISO 14000 standards gaining notoriety, the operational and strategic decisions for environmental managers and businesses is becoming more complex. This paper integrates these elements and their attributes into a strategic assessment and decision tool using the systems with feedback or analytical network process (ANP) technique first introduced by Saaty. The ANP technique, which has been sparingly investigated by researchers or applied by practitioners is useful for modeling dynamic strategies systemic influences on managerial decisions.     

CIMS项目网络计划技术中成本优化算法研究

现有的网络计划在描述项目时已不能适应越来越大型和复杂的C IM S项目,为此,对现有网络计划中任务的约束条件及逻辑关系进行了扩充,并给出了扩充网络计划中时间参数的计算.在此基础上,提出了一种基于样本的成本优化算法,有效地解决了实际项目中的成本优化问题.     

Evaluating and modelling constructs for e-government decision making

It is now becoming increasingly well understood that the investment andevaluation of electronic government projects is determinant on a number oforganisational, policymaking and decision-making factors, which are determiningthe success or failure of such endeavours. Given the increasing interest in themanner and methods by which public sector projects are implemented as well asevaluated, this paper attempts to synergise contemporary e-government projectmanagement (PM) components and synthesise these with extant principles ofinformation systems evaluation. This is carried out in order to model andunderstand the underlying constructs and determinants of decision-making andoperational dynamics within an electronic government case study. The authorsseek to advance and apply the cognitive mapping technique of Fuzzy CognitiveMapping (FCM), through the use of an interpretivist, empirical enquiry techniquethat is melded with an exploratory simulation of the key factors involved ine-government PM issues. The FCM allows the identification of theinter-relationships within this context and provides a basis for identifyingthose constructs of PM that drive the case study decision-making agenda.Correlative relationships are also highlighted alongside causalinter-relationships among the dynamic interacting nodes of the digraphrepresentation, to fully explore the schema of project evaluation ine-government.     

A vertex oriented approach to the equal remaining obligations rule for minimum cost spanning tree situations

In this paper, we consider spanning tree situations, where players want to be connected to a source as cheap as possible. These situations involve the construction of a spanning tree with the minimum cost as well as the allocation of the cost of this minimum cost spanning tree among its users in a fair way. Feltkamp, Muto and Tijs 1994 introduced the equal remaining obligations rule to solve the cost allocation problem in these situations. Recently, it has been shown that the equal remaining obligations rule satisfies many appealing properties and can be obtained with different approaches. In this paper, we provide a new approach to obtain the equal remaining obligations rule. Specifically, we show that the equal remaining obligations rule can be obtained as the average of the cost allocations provided by a vertex oriented construct-and-charge procedure for each order of players.     

Selection among ranked projects under segmentation,policy and logical constraints

The paper proposes a method for project selection under a specific decision situation, where a final selection is guided by two aspects: (1) satisfaction of certain segmentation, policy and/or logical constraints, and (2) assurance that the individual evaluation of the projects is respected to the maximum degree. This approach is somewhat different than the usual portfolio optimization, where combinations of projects are compared without special concern on respecting the project’s ranking. The entire process is implemented in two phases: the projects are first ranked, usually through a multicriteria approach. The obtained complete preorder of the projects is then used in an integer programming module in order to effectively drive the final selection that satisfies the segmentation and/or logical constraints. The innovative part of the proposed approach is the way it overcomes the well-known bias towards low cost projects which is caused by the knapsack formulation commonly used in the integer programming phase. Actually this is the main source of divergence between the final selection and the initial complete preorder of the projects. The proposed method improves an agreement between the final selection of projects obtained from the integer programming model and the ranking obtained from the multicriteria approach.     

基于AHP-Entropy方法的科技成果转化绩效评价

科技成果的转化绩效优劣需要从多个层次、多个视角进行考核,本文从转化成果的经济效益、社会效益、环境效益和扩散效应等四个方面对科技成果转化绩效进行评价,评价体系的建立力求突出指标的精炼性和数据的可获性,借助AHP-Entropy方法并结合调查数据开展实证分析,阐述了评价方法的操作步骤且验证了评价体系的科学性和实践可行性。     

Further Areas for O.R. Modelling in Industry

This paper sets out the case for OR workers embarking on the construction of models of wider scope than has been traditional. Changing industrial conditions emphasize the need to include the social costs of absenteeism, high labour turnover, training and indifferent quality in the evaluation of new projects, as well as the influence on productivity of these factors, and, more especially, of the means devised to overcome them. New criteria of effectiveness are required.A plea is made for OR to be involved in model building of the new patterns of industrial organization; such models could help the uncommitted countries to explore the alternatives at factory and union levels. A comprehensive model would therefore need also to quantify the effect of alternative union structures and strategies on industrial output and on the living standards of the workers.Quantification presents formidable difficulties but to avoid such problems would condemn OR to a role of perpetual sub-optimization.     

The two-grid interpolating element free Galerkin (TG-IEFG) method for solving Rosenau-regularized long wave (RRLW) equation with error analysis

The two-grid method is a technique to solve the linear system of algebraic equations for reducing the computational cost. In this study, the two-grid procedure has been combined with the EFG method for solving nonlinear partial differential equations. The two-grid FEM has been introduced in various forms. The well-known two-grid FEM is a three-step method that has been proposed by Bajpai and Nataraj (Comput. Math. Appl. 2014;68:2277–2291) that the new proposed scheme is an ecient procedure for solving important nonlinear partial differential equations such as Navier–Stokes equation. By applying shape functions of IMLS approximation in the EFG method, a new technique that is called interpolating EFG (IEFG) can be obtained. In the current investigation, we combine the two-grid algorithm with the IEFG method for solving the nonlinear Rosenau-regularized long-wave (RRLW) equation. In other hand, we demonstrate that solutions of steps 1, 2, and 3 exist and are unique and also we achieve an error estimate for them. Moreover, three test problems in one- and two-dimensional cases are given which support accuracy and efficiency of the proposed scheme.     

公路工程评标中的模糊一致矩阵方法

公路工程评标是一项多目标的复杂决策过程,在公路工程多方案分析评价的层次分析决策中应用模糊一致矩阵方法,有效的避开了模糊综合评判中隶属度确定问题.为公路工程评价方案决策这类定性与定量因素并存、正相关与负相关混杂的多因素、多层次评价提供了另一类有效的评判方法,通过公路工程评标方案的分析得到公路工程方案的排序结果,实例分析证明模糊一致矩阵方法是可行的.     

面向复杂产品系统项目评价专家遴选方法研究

专家遴选是复杂产品系统(CoPS)项目科学评价过程中的重要决策问题,科学合理的遴选专家有利于CoPS项目的实现。CoPS项目的多领域知识集成性和项目任务的模糊不确定性,给项目评价的知识属性识别和专家遴选相对“小”领域的科学判断带来较大困难。在面向CoPS项目评价的专家遴选研究问题上,提出了包含技术领域和任务领域的二元知识分类表征方法,构建了基于直觉模糊相似度的专家知识关联度侧度模型,在此基础上建立了包含专家业绩评价和知识关联度的专家遴选多目标决策模型,并给出了一个航天领域电子元器件项目评价的实例。     

Cost impact of float loss on a project with adjustable activity durations

Although delays to non-critical activities within the float do not always affect the overall completion time of a project, they commonly cause disputes over the impact cost and apportionment resulting from the complexity of resource utilization in construction projects. Therefore, considerable attention has been focused on providing an effective and reliable method for analysing the effects of float loss. Several recent studies have proposed various methods; however, most of these methods are based on the assumption of a fixed duration for each activity or activity-based cost simulation. Few studies have considered the trade-off between time and costs and the integration of project resources. Using genetic algorithms, this study introduces a critical path method (CPM)-modified resource-integrated optimization model and successfully quantifies the impact of float loss on the total cost of the project. The results provide objective quantification for accurately evaluating the impact of within-float delays and facilitate the analysis of the impact of delay claims on cost and apportionment in construction projects.     

Cross-efficiency evaluation with directional distance functions

This paper extends the cross-efficiency evaluation for use with directional distance functions. Cross-efficiency evaluation has been developed with oriented Data Envelopment Analysis (DEA) models, so the extension proposed here is aimed at providing a peer-evaluation of decision making units (DMUs) based on measures that account for the inefficiency both in inputs and in outputs simultaneously. We explore the duality relations regarding the models of directional distance functions and define the cross-efficiencies on the basis of the equivalences with some fractional programming problems. Finally, we address in this new context the problem with the alternate optima for the weights and propose some models that implement different alternative secondary goals.